/*
 Red Black Trees
 (C) 1999  Andrea Arcangeli <andrea@suse.de>
 
 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2 of the License, or
 (at your option) any later version.
 
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 
 linux/include/linux/rbtree.h
 
 To use rbtrees you'll have to implement your own insert and search cores.
 This will avoid us to use callbacks and to drop drammatically performances.
 I know it's not the cleaner way,  but in C (not in C++) to get
 performances and genericity...
 
 Some example of insert and search follows here. The search is a plain
 normal search over an ordered tree. The insert instead must be implemented
 in two steps: First, the code must insert the element in order as a red leaf
 in the tree, and then the support library function rb_insert_color() must
 be called. Such function will do the not trivial work to rebalance the
 rbtree, if necessary.
 
 -----------------------------------------------------------------------
 static inline struct page * rb_search_page_cache(struct inode * inode,
 unsigned long offset)
 {
 struct rb_node * n = inode->i_rb_page_cache.rb_node;
 struct page * page;
 
 while (n)
 {
 page = rb_entry(n, struct page, rb_page_cache);
 
 if (offset < page->offset)
 n = n->rb_left;
 else if (offset > page->offset)
 n = n->rb_right;
 else
 return page;
 }
 return NULL;
 }
 
 static inline struct page * __rb_insert_page_cache(struct inode * inode,
 unsigned long offset,
 struct rb_node * node)
 {
 struct rb_node ** p = &inode->i_rb_page_cache.rb_node;
 struct rb_node * parent = NULL;
 struct page * page;
 
 while (*p)
 {
 parent = *p;
 page = rb_entry(parent, struct page, rb_page_cache);
 
 if (offset < page->offset)
 p = &(*p)->rb_left;
 else if (offset > page->offset)
 p = &(*p)->rb_right;
 else
 return page;
 }
 
 rb_link_node(node, parent, p);
 
 return NULL;
 }
 
 static inline struct page * rb_insert_page_cache(struct inode * inode,
 unsigned long offset,
 struct rb_node * node)
 {
 struct page * ret;
 if ((ret = __rb_insert_page_cache(inode, offset, node)))
 goto out;
 rb_insert_color(node, &inode->i_rb_page_cache);
 out:
 return ret;
 }
 -----------------------------------------------------------------------
 */

#include <stdio.h>

namespace newera_network{
	
	struct rb_node
	{
		unsigned long  rb_parent_color;
#define	RB_RED		0
#define	RB_BLACK	1
		struct rb_node *rb_right;
		struct rb_node *rb_left;
	} __attribute__((aligned(sizeof(long))));
    /* The alignment might seem pointless, but allegedly CRIS needs it */
	
	struct rb_root
	{
		struct rb_node *rb_node;
	};
	
	
#define rb_parent(r)   ((struct rb_node *)((r)->rb_parent_color & ~3))
#define rb_color(r)   ((r)->rb_parent_color & 1)
#define rb_is_red(r)   (!rb_color(r))
#define rb_is_black(r) rb_color(r)
#define rb_set_red(r)  do { (r)->rb_parent_color &= ~1; } while (0)
#define rb_set_black(r)  do { (r)->rb_parent_color |= 1; } while (0)
	
	static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
	{
		rb->rb_parent_color = (rb->rb_parent_color & 3) | (unsigned long)p;
	}
	static inline void rb_set_color(struct rb_node *rb, int color)
	{
		rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
	}
	
#define RB_ROOT	(struct rb_root) { NULL, }
#define	rb_entry(ptr, type, member) container_of(ptr, type, member)
	
#define RB_EMPTY_ROOT(root)	((root)->rb_node == NULL)
#define RB_EMPTY_NODE(node)	(rb_parent(node) == node)
#define RB_CLEAR_NODE(node)	(rb_set_parent(node, node))
	
	extern void rb_insert_color(struct rb_node *, struct rb_root *);
	extern void rb_erase(struct rb_node *, struct rb_root *);
	
	typedef void (*rb_augment_f)(struct rb_node *node, void *data);
	
	extern void rb_augment_insert(struct rb_node *node,
								  rb_augment_f func, void *data);
	extern struct rb_node *rb_augment_erase_begin(struct rb_node *node);
	extern void rb_augment_erase_end(struct rb_node *node,
									 rb_augment_f func, void *data);
	
	/* Find logical next and previous nodes in a tree */
	extern struct rb_node *rb_next(const struct rb_node *);
	extern struct rb_node *rb_prev(const struct rb_node *);
	extern struct rb_node *rb_first(const struct rb_root *);
	extern struct rb_node *rb_last(const struct rb_root *);
	
	/* Fast replacement of a single node without remove/rebalance/add/rebalance */
	extern void rb_replace_node(struct rb_node *victim, struct rb_node *new_node, 
								struct rb_root *root);
	
	static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
									struct rb_node ** rb_link)
	{
		node->rb_parent_color = (unsigned long )parent;
		node->rb_left = node->rb_right = NULL;
		
		*rb_link = node;
	}
};